I voted for Longevity. Longevity never even gets built! And, why exactly do I need double growth at this point? 1000 shields too!
At least the Great Wall gives me a couple culture points all game - and it looks cool. It's culture value should be higher than 2.
To me, the Oracle isn't the worst, because it can make some people happy at an early stage when I may not have many luxuries or military support. It comes at a time when I really don't have much money for entertainment. Plus, it gives good culture over the game.
Also, Shakespeare's isn't the worst. At least I can get a WLTK day out of a city. Or, I could do a massive draft there. And it gives great culture points.
I play with Player1's mod that changes the modern wonders a bit, making them more worth it.